Supernatural Little Sister

IT

Hello!
I've been thinking about writing a Supernatural/It crossover for a long time and here it is! While I have tried to implement a lot of details from Stephen King's "It," this chapter should still be enjoyable even if you haven't read the book or watched the movie.
Enjoy!

Allison: 16
Dean: 25
Sam: 22

     "I'm telling you, this lobster roll is the best damn thing you'll eat in your life, Al." Dean turns up the music and Sam gives him a look.
     "It better be good. We're going, like, 10 hours out of the way." Allison sighs, resting her head on the window.
     Things have been off ever since Dean sold his soul for Sam a few months ago. He keeps taking them on these impulsive detours and refuses to talk about what's bound to happen in ten months. All the while, Allison knows that Sam feels guilty about everything, even though no one forced Dean to do this. Sometimes it feels like Dean wanted to do this.
     "Shit," Dean mutters, taking the closest exit.
     "What?" Sam says.
     "We need gas. Damn, we were almost there too." Dean sighs and checks on Allison in the rear view mirror. "Sorry, kid, we'll get some lunch soon."
     "Derry, Maine," Sam reads off of a sign they pass on the way into town.
     "Never heard of it," Allison says, as Dean turns onto a street and pulls into a dated gas station.
     "Me neither but I'm gonna take a leak. Ally, fill the car up," Dean says, tossing his sister one of their stolen credit cards.
     "Wha—" Dean cuts off her complaints with a slam of the car door.
     "Youngest always does it." Sam shrugs and Allison begrudgingly gets out of the car.
     She approaches one of the two rickety looking gas pumps and cringes at the puddle of gas that pools around the base of the pump. Allison tucks a piece of her blonde hair behind her ear and pulls out the credit card. Her eyes search for the slot to stick it in, but this gas station must've been built long before "paying at the pump."
     "Sam, there's no slot for the card!" Allison shouts to Sam and he gives her a confused look.
     "Never mind." She sighs and heads inside the gas station.
     Chimes clink as Allison pushes the dirty glass door open and an old woman behind the counter smiles at her.
     "Hello! How may I help you?" The sweet old woman asks.
     "Oh, I was just wondering if I could pay for a tank of gas? We're at the second pump." Allison hands her the card and the woman smiles.
     "Of course!" The woman takes the card from Allison and pulls out an ancient looking credit card reader. "Anything else for you today?"
     "I think I'm good—"
     "Are you sure? We have lots of treats! How about some candy? A sweet little girl like yourself could always use some candy." The woman turns around, searching for candy in the shelves behind her. Allison's eyes look around the gas station and she now notices how the shelves are practically barren and the tiles on the floor are cracked and filthy. The slight stench of something burning crawls inside her nose and she nervously looks towards the door.
     "Just the gas. Please." Allison's stomach churns at the thought of staying in this gas station any longer.
     "No...treats?" The woman slowly turns around to face Allison. Her soft and cheery face has morphed into the face of a hideous witch. She starts to drool and sputter as she reaches towards Allison, gnashing her sharp teeth.
     "What about a root beer float, Al? You wanna FLOAT?" A distorted voice booms in Allison's head.
     "Please, stop!"
     "Miss, do you need cash back?" The woman asks cheerily. Allison stares at the cheery woman, horrified.
     "N-no. Just the gas." Allison shivers as the woman hands her back the credit card.
     "You fill her up?" Dean asks as he exits the bathroom. He puts a hand on Allison's shoulder, making her jump. "You good?"
     "Yeah, yeah. I just need to fill the car up." Allison swallows and looks out towards the Impala. While she intended to check on Sam, her gaze quickly meets a red balloon that floats freely in the cloudy afternoon sky.
     "Okay, weirdo. Come on." Dean leads the way out of the gas station and waves to the cashier. "Have a good one, m'am!"
     As Dean guides Allison out the door, Allison turns her head and quickly glances at the cashier. The old woman stares intently at Allison and a snake like tongue flicks out of her mouth, moistening her dry, wrinkly lips.
     "You too, kiddos! Welcome to Derry!"